From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756302Ab1I2JtZ (ORCPT ); Thu, 29 Sep 2011 05:49:25 -0400 Received: from cantor2.suse.de ([195.135.220.15]:48809 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756289Ab1I2JtX (ORCPT ); Thu, 29 Sep 2011 05:49:23 -0400 Date: Thu, 29 Sep 2011 11:49:18 +0200 From: Michal Hocko To: Johannes Weiner Cc: Andrew Morton , KAMEZAWA Hiroyuki , Daisuke Nishimura , Balbir Singh , Ying Han , Greg Thelen , Michel Lespinasse , Rik van Riel , Minchan Kim , Christoph Hellwig , linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [patch 06/11] mm: memcg: remove optimization of keeping the root_mem_cgroup LRU lists empty Message-ID: <20110929094918.GA21113@tiehlicka.suse.cz> References: <1315825048-3437-1-git-send-email-jweiner@redhat.com> <1315825048-3437-7-git-send-email-jweiner@redhat.com> <20110920150229.GB3571@tiehlicka.suse.cz> <20110929092033.GB6050@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20110929092033.GB6050@redhat.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu 29-09-11 11:20:33, Johannes Weiner wrote: > On Tue, Sep 20, 2011 at 05:02:29PM +0200, Michal Hocko wrote: > > On Mon 12-09-11 12:57:23, Johannes Weiner wrote: > > > root_mem_cgroup, lacking a configurable limit, was never subject to > > > limit reclaim, so the pages charged to it could be kept off its LRU > > > lists. They would be found on the global per-zone LRU lists upon > > > physical memory pressure and it made sense to avoid uselessly linking > > > them to both lists. > > > > > > The global per-zone LRU lists are about to go away on memcg-enabled > > > kernels, with all pages being exclusively linked to their respective > > > per-memcg LRU lists. As a result, pages of the root_mem_cgroup must > > > also be linked to its LRU lists again. > > > > Nevertheless we still do not charge them so this should be mentioned > > here? > > Added for the next revision: > > "This is purely about the LRU list, root_mem_cgroup is still > not charged." OK, that should be more clear. Thanks! -- Michal Hocko SUSE Labs SUSE LINUX s.r.o. Lihovarska 1060/12 190 00 Praha 9 Czech Republic